the back of a receiver, integrated amplifier or power
amplifier.
Midrange:
The frequency span in the middle of the audio
range, roughly 180Hz - 3000Hz. Also used to describe
the driver that reproduces these frequencies.
Ohm:
A unit of electrical resistance. That which opposes
an electric current in a conductor. In audio, a measure of
the load presented by a device to an electrical source.
Out-of-Phase:
The polarity of an audio signal when con-
nected as follows: (+) to (-) and (-) to (+).
Passive:
Uses no electrical power.
Phase:
An expression of the relative polarities of two sig-
nals.
Power Handling:
The ability of a loudspeaker to operate
without large increases in distortion when given varying
amounts of input power.
Preamplifier:
An electronic device that selects sources
and passes line-level signals to an amplifier.
Pre-Out:
A preamp line-level RCA output on the back of
a receiver, integrated amplifier or preamplifier.
Receiver:
A preamplifier, amplifier and tuner built into
one chassis.
Satellite:
Front L & R speakers when used with a sub-
woofer. Also referred to as "main speakers".
Sensitivity:
A ratio of voltage across the speaker load to
the acoustic power output, measured in decibels.
Sub Out:
An line level output for connection to a sub-
woofer or subwoofer signal processor.
Subwoofer:
A driver designed to operate over the low
bass portion of the audio range. Also refers to a system
consisting of a woofer and its enclosure, which are phys-
ically separate from the upper range loudspeakers.
Surround Speakers:
Speakers located in the side or
rear for surround channel effects.
Treble:
The upper part of the frequency spectrum, con-
sisting of frequencies above about 3000Hz.
Tweeter:
A small driver designed to reproduce high fre-
quencies.
Watt:
A measure of electrical power, combining the volt-
age with the electrical current required to drive the loud-
speaker.
Weight:
Low frequencies below 50Hz.
Woofer:
A driver designed to operate over the bass por-
tion of the audio range.
